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Design of Mechatronic systems: An integrated inter-departmental curriculum
Mechatronics Vol. 5, No. 7, pp. 845-853, 1995 © 1995 Elsevier Science Ltd Printed in Great Britain. All rights reserved. 13957-4158/95 $9.50+0.00
Pergamon 0957-4158 (95) 00045-3
DESIGN OF MECHATRONIC SYSTEMS: AN INTEGRATED INTER-DEPARTMENTAL CURRICULUM GIORGIO RIZZONI* and ALl KEYHANI* *Department of Mechanical Engineering and tDepartment of Electrical Engineering, The Ohio State University, Columbus, OH 43210, U.S.A.
Abstract--Some early steps in the development of an inter-disciplinary Mechatronics curriculum at the Ohio State University are described. More specifically, this paper reports on the mid-course results of an undergraduate curriculum development grant funded by the National Science Foundation* Division of Undergraduate Education, and managed by the authors of this paper. The aim of the grant is to foster the development of an inter-departmental, inter-disciplinary curriculum in Mechatronics. The specific effort described in this paper represents only a part of the educational and research activities in the field of electro-mechanical systems at the Ohio State University.
INTRODUCTION Many of today's machines and processes are of an electro-mechanical nature. Examples of electro-mechanical systems are found in m a n y automotive, aerospace, manufacturing, test and instrumentation, consumer and industrial electronics applications, and in m a n y other fields of engineering. The extensive use of microelectronics in manufacturing systems and in engineering products and processes has led to a new approach to the design of such engineering systems. To quote a term coined in Japan and widely adopted in Europe, mechatronic design has surfaced as a new philosophy of design, based on the integration of existing disciplines--primarily mechanical, and electrical, electronic and software engineering. Some of the distinguishing features of the mechatronic approach to the design of products and processes are [1]: the
replacement of many mechanical functions with electronic ones, resulting in much greater flexibility; ease of re-design or re-programming; the ability to implement distributed control in complex systems; and the ability to conduct automated data collection and reporting. In essence, mechatronic design is the confluence of the traditional design methods with sensors and instrumentation technology, drive and actuator technology, and e m b e d d e d real-time microprocessor systems and real-time software. Mechatronic systems range from heavy industrial machinery, to vehicle propulsion systems, to precision electromechanical motion control devices, to consumer products. Although both mechanical and electrical engineers are typically employed by companies which design, test, and manufacture electro-mechanical products, there is
*NSF Grant DUE-9354403. 845
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t). R1ZZONI and A. KEYHAN1
also a need for engineers with a more in-depth knowledge of both mechanical and electrical and electronic devices and systems. Electro-Mechanical engineers should be able to integrate the two disciplines so as to deal efficiently with the design and analysis of electro-mechanical products. The Electro-Mechanical System Design curriculum that is currently under development at the Ohio State University (OSU) offers the opportunity to develop these skills [2]. Other efforts in this area have recently been documented in [3]. A very important issue, which is often neglected in a strictly disciplinary approach to engineering education, is the integrated aspect of engineering practice, which is unavoidable in the design and analysis of large scale and/or complex systems. Another aim of the effort described in this paper is to develop a curriculum that will provide students with exposure to the integration of electrical, electronic, mechanical and software engineering, making use of the most modern CAD tools available, and supplementing the analytical and computational experience with a hands-on laboratory and with self-teaching modules to provide background for more advanced topics.
BACKGROUND
The Departments of Electrical and Mechanical Engineering at OSU have a rich history of collaboration, especial b ill research projects centered around the design analysis and control of electro-mechanical systems. Among the most notable aspects of this collaboration arc the Adaptive Walking Machine, developed through the 1980s, which led to an ongoing collaboration between the Electrical and Mechanical Engineering Departments in the field of Robotics research and education. More recently, the creation of an inter-disciplinary Center for Automotive Research with major funding from the automotive industry: the establishment of an endowed Chair of Electro-Mechanical Systems by the Ford Motor Company, consisting of a joint appointment in the Electrical and Mechanical Engineering Departments: and the N S F - D U E curriculum development grant mentioned above, have strengthened the existing ties, and have fostered interest in the development of more comprehensive curricula, graduate as well as undergraduate, in the field of Mechatronics.
GOALS OF THE P R O J E C T The principal goals of this project are to establish a pilot program to prove the feasibility of an inter-disciplinary, inter-departmental curriculum in Mechatronics. Although the aim and scope of the program described in this paper are limited to a special class of mechatronic systems, we hope that the project will in time provide the momentum necessary to develop a comprehensive program. More specific objectives of the project are listed below. (i) To develop an innovative curriculum as part of a comprehensive program in Electro-Mechanical System Design. with special focus on automotive applications and hybrid-electric propulsion systems.
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(ii) To use this curriculum as a means of integrating electrical, electronic, mechanical, and software engineering education into a capstone design sequence. (iii) To emphasize the use of a variety of CAD tools in engineering design and analysis, and to explore self-instruction in the laboratory through videos and software. (iv) To provide an applied engineering problem setting in a specially designed electro-mechanical systems laboratory, enabling the students to address design and experimental issues in engineering with industrial support and participation. H The application focus on vehicles and vehicle propulsion systems is a natural one at OSU, due to the existing research focus on electric vehicles, vehicle dynamics, and internal combustion engine and emissions control. The resulting synergy between research and education already provides a lively and exciting interaction among faculty and undergraduate students. Further, as industrial support of the experimental facilities begins to materialize, this innovative curriculum will also serve the purpose of establishing a bridge between the needs of industry for well-trained engineers with an interdisciplinary education, and OSU engineering graduates. The choice of the automotive industry as a target of industrial application is not coincidental; the automotive industry is the major contributor to the national economy, and has long recognized the need for interdisciplinary training in engineering with emphasis on design and experimental skills. Additional industrial support is also expected from the electro-mechanical industry in the State of Ohio.
STRUCTURE OF THE CURRICULUM 1. Course work
The three courses that will form the core sequence of the program are: Introduction to Mechatronics Electro-Mechanical Motion Devices Modeling and Control o f Industrial Electric Machines
These courses and the laboratory can be integrated into the existing Electrical and Mechanical Engineering curricula, and will culminate in a capstone design project centered around the facilities available in the laboratory (described below). This setting will permit the development of a curriculum in electro-mechanical systems with a focus on real engineering problems for electrical and mechanical engineering students. Through this curriculum we seek to lead the undergraduate students to creatively identify capstone design projects in electro-mechanical systems. The design projects will be realized through the use of open laboratories and with the participation of industrial sponsors, who will assist in defining projects and will provide in-kind and cash support for individual projects. The typical curriculum will consist of three major components, in addition to the basic requirements common to all engineering degrees at OSU. First, a minimum set of preparatory topics must be covered by all students in the program (whether electrical or mechanical engineering majors). These are considered to be core courses
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for the program. Next, the students will select an area of specialization within the discipline of Electro-Mechanical Systems. The pilot program described here focuses on automotive electric and hybrid-electric propulsion systems. Other similar concentrations can easily be identified in the future, if faculty interest exists. For example, there already exist very strong programs at least in the following areas: robotics', control systems; precision measurements: manufacturing systems; fluid power systems; vibrations; power electronics. The students will also be expected to complete a senior design project with special focus on one of the areas described above. The Electro-Mechanical Systems Laboratory is but one example of the options available to students interested in pursuing such a curriculum. Finally, the students will select a number of technical electives from the available list of courses in the two participating departments. A possible sequence is indicated below. Core courses • • • • • • •
Introductory Circuits (with Laboratory) Introductory Electronics (with Laboratory l Introduction to Logic Design (with Laboratory) Introduction to Microprocessor Based Systems System Dynamics and Vibrations (with Laboratory) System Dynamics and Electro-Mechanics (with Laboratory) Mechanical Measurements (with Laboratory) Specialization courses
• • • •
Introduction to Mechatronics Dynamics and Simulation of Electro-Mechanical Systems Control of Electro-Mechanical Systems Electro-Mechanical Systems Laboratory; Senior Design Project, to be elected over two or three consecutive quarters.
Further detail oil the three lecture courses, which have been specially developed or modified to be part of this program, is supplied in the Appendix. Technical electives Students in the program will be required to complete 9-15 quarter hours of technical electives to be chosen among the following and other existing courses: • • • • • • •
Machinery Dynamics and Vibration Measurement System Application and Design Applied Digital Control Fluid Power Systems Mechanical Design of Manipulators and Robots Microprocessor Laboratory Introduction to Real-time Robotics Systems.
Several other relevant courses are available in both Departments.
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2. Laboratory The Electro-Mechanical Systems Laboratory is designed to expose the students to the electrical, electronic, mechanical, hydraulic and software aspects of mechatronic systems. Applications that will be studied in this laboratory will include: an electromagneto-mechanical proportional effort steering system; an anti-lock braking system; a hydraulic load; a flexible shaft with inertia and friction loads; hydraulic systems; and electric and hybrid-electric vehicle applications. The laboratory, which is already partially operating, includes a number of experiment stations, including a small internal combustion engine and various electric machines, such as induction, synchronous, D.C., and switched reluctance motors. Each station is or will be equipped with either a Motorola DSP 56000 Digital Signal Processor or a Motorola MC68332 microcontroller development system. Workstations are available for data acquisition, simulation studies and data processing. The laboratory will function as an open laboratory, available to the students for their design projects. It is expected that a formal laboratory course will be developed in the future. Additional laboratory facilities for special projects are also available in the OSU Center for Automotive Research. The existing experimental facilities reflect the interests of the industries currently sponsoring the program (see Acknowledgements). It is expected that the majority of the senior design projects will be industrysponsored.
3. Design projects The design projects will be realized through the use of open laboratories and with the participation of industrial sponsors, who will assist in defining projects and will provide in-kind and cash support for individual projects. Listed below are some sample projects that are currently in progress.
Formula Lightning TM electric race car. This project involves the design, analysis and testing of an electric open-wheel race car. The student-designed propulsion and energy storage systems were tested in inter-university competitions in 1994 and 1995. Projects have included: vehicle dynamics and race track simulation; motor and battery pack selection; battery pack and loading system design; and transmission and driveline design. This is an ongoing competition, and new projects are defined in advance of each race season. Four races are scheduled for 1995. The OSU vehicle was the winner of the 1994 Electricore Inaugural Formula Lightning Race at Indianapolis Raceway Park. This race was nationally televised on ESPN. A number of industrial sponsors funded this event. Design of an electro-mechanical valve for power steering system. If the camshaft of an automobile or the hydraulic rotary valve used in the power steering system could be replaced by an electro-mechanically controlled valve, the car would run more efficiently. The objective of this project is to design a laboratory scale model of an electro-mechanically controlled valve to be operated with a Motorola M68HCllE9 microcontroller. This project will consist of the design of a solenoid operated valve, a power converter to provide the power needed by the valve and a base drive board.
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The microcontroller will be interfaced with the drive base board for control of the power converter that will control the solenoid valve. The control software will reside in the microcontroller for the operation of the valve that will permit the study of various control strategies.
Design of a fuel injection system :or small utility engines. The aim of this project is to design a fuel injection retrofit system for a small utility engine based on the Motorola MC68332 microcontroller. New regulations issued by the U.S. Environment Protection Agency require that small engines begin to comply with the environmental standards currently imposed on passenger and commercial vehicles. This project will include the design of the fuel injector driver electronics and of a control software development system that will permit rapid prototyping of different fuel control strategies.
CREATING A PIPELINE
One of the difficulties in the establishment of new programs is in attracting a sufficient number of students to the program, so that critical mass is established. To provide motivation to enter a program that is likely to be more challenging than the conventional BSEE and BSME curricula, some special incentives have been created, based on industrial support, internal (College) support, and on the facutty's own research programs. These include the following. • Use of the College of Engineermg Honors Program and of numerous available scholarships to support students through their senior year. • Use of National Science Foundation Research Experience for Undergraduates* grant program to provide student support. • Use of industry-supplied scholarships to recruit promising students, with special consideration to women and minorities. • Summer internships in industry, provided by industrial sponsors.
PROGRAM EVALUATION
The curriculum program described in the preceding sections will be assessed and evaluated by two principal means. The first consists of an Industry-University Advisory Board, which will advise and guide the course and laboratory development. The members of the advisory board will be as follows. (1) The Chairs of each Departtnent, cx .ffficio. (2) One faculty with significant experience in Electro-Mechanical Systems from each Department. (3) A board of industrial advisors. Current members of the advisory board are from: Chrysler Corporation: Ford Motor Company: General Motors (three divisions): Liebert: Reliance Electric: Motorola. *This program provides funds for the support of undergraduate students to NSF research grant recipients.
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The second means of evaluation consists of a statistical survey done be specialists (i.e. from the O S U School of Education); the statistical survey will track students in the program, as well as a control group of engineering students not enrolled in the certificate program. Questionnaires will be designed by the evaluation team in collaboration with the industrial sponsors, with the aim of establishing relevant measures. In the last year of the study, students who have graduated from the program, as well as a control group, will be asked to fill a separate questionnaire aimed at determining the success of the program in preparing engineering students for their careers.
CONCLUSION The project described in this paper incorporates the major elements which lie at the core of the engineering education mission in the 21st century*: (i) a new emphasis on basic engineering for design and production; (ii) the integration of mechanical, electronic and computational systems; (iii) multi-media tools to provide a more flexible learning environment; (iv) an environment in which the undergraduate education process naturally integrates with research activities, thus fostering the transfer of ideas and expertise from research to education. The alliance between industry and university that is outlined in this paper should be a natural one in engineering education; we hope that in time the O S U program may serve as a model for the development of a new generation of electro-mechanical engineers with truly interdisciplinary skills. It is hoped that the educational initiative undertaken by these authors provides a building block towards a comprehensive Mechatronics program at OSU. Acknowledgements--The work described in this paper has been supported principally through a grant from the National Science Foundation Division of Undergraduate Education, and with matching equipment and in-kind contributions from the OSU Center for Automotive Research, the OSU Office of Research, the Departments of Electrical and Mechanical Engineering, and the OSU Engineering Experiment Station. Cash and equipment gifts from Ford Motor Company, General Motors Corporation, Liebert, Reliance Electric and Motorola, Inc., are alsogratefully acknowledged. Finally, the authors would like to thank the sponsors of the Formula Lightning~ electric race car: Ohio Semitronics, Inc.; General Motors; the International Brotherhood of Electrical Workers, Local 683; PPG; Transportation Research Center, Inc.; Ohio Aerospace Institute; Edison Welding Institute; Honda of America; Taylor Race Engineering; Watterson Industries; Electric Vehicle TechnologyCompetitions, Inc.; Electricore.
REFERENCES 1. Bradley D. A., Dawson D., Burd N. C. and Loader A. J., Mechatronics, Electronics in Products and Processes. Chapman & Hall, London (1991). 2. Rizzoni G. and Keyhani A., Design of Mechatronic Systems: an integrated, inter-departmental curriculum. In Proceedings of First Workshop on Mechatronics Education, Stanford, CA, 21-22 July (1994). 3. Carryer J. E. (Ed.), Proceedings of First Workshop on Mechatronics Education, Stanford, CA, 21-22 July (1994). 4. Rizzoni G., Principles and Applications of Electrical Engineering. Richard D. Irwin, Burr Ridge, IL (1993). *Based on the keynote address given by Dr Charles M. Vest at the 1992 annual conference of the ASEE.
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APPENDIX INTRODUCTION
TO MECHATRONICS
Course objectives The aim of this course is to supply basic background in the areas of multi-domain systems (including fluid, thermal, mechanical, electro-mechanical, electronic). Among the topics covered are: multi-phase A.C. power, power electronics, and digital computer interface. The course summarizes specialized material necessary to understand the operation of electro-mechanical systems which is currently not covered in the ME curriculum, and which is scattered among several courses in the EE curriculum. The material presented in the course is subdivided into three main sections: (i) modeling hybrid systems; (ii) signal conditioning and digital computer interface fundamentals; and (iii) power electronics for industrial applications. During the course various case studies will be presented to illustrate the application of modern electronics to mechanical systems. These exercises will take advantage of computer-aided tools such as SABER/Analogy which permit the modeling of mixed-mode electro-mechanical, electro-magneto-mechanical and electro-hydro-mechanical systems. At the conclusion of the course the student will be able to analyze and specify electronic systems with application to the control of industrial machinery using state-of-the-art computer aids. Student performance will be assessed through examinations (one midterm and one final exam), and through homework assignments, including computer-aided design problems.
Text Rizzoni G., Principles and Applications of Electrical Engineering. Richard D. Irwin, Burr Ridge, IL (1993). Rizzoni Q., Class notes, The Ohio State University, Columbus, OH.
Reference SABER/Analogy user's guide, Analogy (1992).
E L E C T R O - M E C H A N I C A L MOTION DEVICES Course objectives The purpose of this course is to provide a basic knowledge of electro-mechanical motion devices for mechanical and electrical engineering students interested in electro-mechanical systems, robotics and control. To achieve this objective, considerable attention is given to electro-mechanical rotational devices commonly used in automated control systems. The course summarizes background material needed for mechanical engineering students to understand the operation of electro-mechanical motion devices. The material presented in the course consists of the following sections: (a) magnetic circuits; (b) electro-mechanical energy conversion; (c) state space model representation; (d) design of magnetically coupled windings; (e) dynamic models of D.C. machines; and (f) A.C. electro-mechanical motion devices. During the course various problems are assigned to study the dynamic performance of electro-mechanical motion devices. The problems are studied using computer-aided design tools of the Matlab software system. Student performance is evaluated through five simulation problems and one midterm and a Final exam.
M O D E R N CONTROL OF INDUSTRIAL ELECTRIC MACHINES Course objectives The aim of this course is to provide basic knowledge of modern control techniques used for control of industrial electric machines as part of electro-mechanical systems such as electric vehicles and manufacturing systems. The course is presented from a system viewpoint with the objectives to provide knowledge needed by mechanical and electrical engineering students for designing electro-mechanical systems using industrial electric machines. The material presented in the course consists of the following sections: (a) electric motor drive systems; (b) modeling of the three-phase A.C. machines in arbitrary reference frames; (c) simulation of power
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converters; (d) modeling of Pulse-Width-Modulated (PWM) Inverters; (e) current control of PWM inverters; (f) A.C. drives' stator voltage and frequency control; (g) vector control and flux weakening control. During the course six simulation problems are assigned to study the control of an A.C. machine supplied from a power converter using various control techniques. The problems are studied using computer design tools of the Matlab software system. Students' performance is evaluated through six simulation problems, one take home midterm and a final exam. Text
Krause P. and Wasynczuk O., Electromechanical Motion Devices. McGraw-Hill, New York (1989). References Power Electronics and A C Drives. Prentice-Hall, Englewood Cliffs, NJ (1986). Keyhani A., Class notes.
Pergamon 0957-4158 (95) 00045-3
DESIGN OF MECHATRONIC SYSTEMS: AN INTEGRATED INTER-DEPARTMENTAL CURRICULUM GIORGIO RIZZONI* and ALl KEYHANI* *Department of Mechanical Engineering and tDepartment of Electrical Engineering, The Ohio State University, Columbus, OH 43210, U.S.A.
Abstract--Some early steps in the development of an inter-disciplinary Mechatronics curriculum at the Ohio State University are described. More specifically, this paper reports on the mid-course results of an undergraduate curriculum development grant funded by the National Science Foundation* Division of Undergraduate Education, and managed by the authors of this paper. The aim of the grant is to foster the development of an inter-departmental, inter-disciplinary curriculum in Mechatronics. The specific effort described in this paper represents only a part of the educational and research activities in the field of electro-mechanical systems at the Ohio State University.
INTRODUCTION Many of today's machines and processes are of an electro-mechanical nature. Examples of electro-mechanical systems are found in m a n y automotive, aerospace, manufacturing, test and instrumentation, consumer and industrial electronics applications, and in m a n y other fields of engineering. The extensive use of microelectronics in manufacturing systems and in engineering products and processes has led to a new approach to the design of such engineering systems. To quote a term coined in Japan and widely adopted in Europe, mechatronic design has surfaced as a new philosophy of design, based on the integration of existing disciplines--primarily mechanical, and electrical, electronic and software engineering. Some of the distinguishing features of the mechatronic approach to the design of products and processes are [1]: the
replacement of many mechanical functions with electronic ones, resulting in much greater flexibility; ease of re-design or re-programming; the ability to implement distributed control in complex systems; and the ability to conduct automated data collection and reporting. In essence, mechatronic design is the confluence of the traditional design methods with sensors and instrumentation technology, drive and actuator technology, and e m b e d d e d real-time microprocessor systems and real-time software. Mechatronic systems range from heavy industrial machinery, to vehicle propulsion systems, to precision electromechanical motion control devices, to consumer products. Although both mechanical and electrical engineers are typically employed by companies which design, test, and manufacture electro-mechanical products, there is
*NSF Grant DUE-9354403. 845
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t). R1ZZONI and A. KEYHAN1
also a need for engineers with a more in-depth knowledge of both mechanical and electrical and electronic devices and systems. Electro-Mechanical engineers should be able to integrate the two disciplines so as to deal efficiently with the design and analysis of electro-mechanical products. The Electro-Mechanical System Design curriculum that is currently under development at the Ohio State University (OSU) offers the opportunity to develop these skills [2]. Other efforts in this area have recently been documented in [3]. A very important issue, which is often neglected in a strictly disciplinary approach to engineering education, is the integrated aspect of engineering practice, which is unavoidable in the design and analysis of large scale and/or complex systems. Another aim of the effort described in this paper is to develop a curriculum that will provide students with exposure to the integration of electrical, electronic, mechanical and software engineering, making use of the most modern CAD tools available, and supplementing the analytical and computational experience with a hands-on laboratory and with self-teaching modules to provide background for more advanced topics.
BACKGROUND
The Departments of Electrical and Mechanical Engineering at OSU have a rich history of collaboration, especial b ill research projects centered around the design analysis and control of electro-mechanical systems. Among the most notable aspects of this collaboration arc the Adaptive Walking Machine, developed through the 1980s, which led to an ongoing collaboration between the Electrical and Mechanical Engineering Departments in the field of Robotics research and education. More recently, the creation of an inter-disciplinary Center for Automotive Research with major funding from the automotive industry: the establishment of an endowed Chair of Electro-Mechanical Systems by the Ford Motor Company, consisting of a joint appointment in the Electrical and Mechanical Engineering Departments: and the N S F - D U E curriculum development grant mentioned above, have strengthened the existing ties, and have fostered interest in the development of more comprehensive curricula, graduate as well as undergraduate, in the field of Mechatronics.
GOALS OF THE P R O J E C T The principal goals of this project are to establish a pilot program to prove the feasibility of an inter-disciplinary, inter-departmental curriculum in Mechatronics. Although the aim and scope of the program described in this paper are limited to a special class of mechatronic systems, we hope that the project will in time provide the momentum necessary to develop a comprehensive program. More specific objectives of the project are listed below. (i) To develop an innovative curriculum as part of a comprehensive program in Electro-Mechanical System Design. with special focus on automotive applications and hybrid-electric propulsion systems.
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(ii) To use this curriculum as a means of integrating electrical, electronic, mechanical, and software engineering education into a capstone design sequence. (iii) To emphasize the use of a variety of CAD tools in engineering design and analysis, and to explore self-instruction in the laboratory through videos and software. (iv) To provide an applied engineering problem setting in a specially designed electro-mechanical systems laboratory, enabling the students to address design and experimental issues in engineering with industrial support and participation. H The application focus on vehicles and vehicle propulsion systems is a natural one at OSU, due to the existing research focus on electric vehicles, vehicle dynamics, and internal combustion engine and emissions control. The resulting synergy between research and education already provides a lively and exciting interaction among faculty and undergraduate students. Further, as industrial support of the experimental facilities begins to materialize, this innovative curriculum will also serve the purpose of establishing a bridge between the needs of industry for well-trained engineers with an interdisciplinary education, and OSU engineering graduates. The choice of the automotive industry as a target of industrial application is not coincidental; the automotive industry is the major contributor to the national economy, and has long recognized the need for interdisciplinary training in engineering with emphasis on design and experimental skills. Additional industrial support is also expected from the electro-mechanical industry in the State of Ohio.
STRUCTURE OF THE CURRICULUM 1. Course work
The three courses that will form the core sequence of the program are: Introduction to Mechatronics Electro-Mechanical Motion Devices Modeling and Control o f Industrial Electric Machines
These courses and the laboratory can be integrated into the existing Electrical and Mechanical Engineering curricula, and will culminate in a capstone design project centered around the facilities available in the laboratory (described below). This setting will permit the development of a curriculum in electro-mechanical systems with a focus on real engineering problems for electrical and mechanical engineering students. Through this curriculum we seek to lead the undergraduate students to creatively identify capstone design projects in electro-mechanical systems. The design projects will be realized through the use of open laboratories and with the participation of industrial sponsors, who will assist in defining projects and will provide in-kind and cash support for individual projects. The typical curriculum will consist of three major components, in addition to the basic requirements common to all engineering degrees at OSU. First, a minimum set of preparatory topics must be covered by all students in the program (whether electrical or mechanical engineering majors). These are considered to be core courses
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for the program. Next, the students will select an area of specialization within the discipline of Electro-Mechanical Systems. The pilot program described here focuses on automotive electric and hybrid-electric propulsion systems. Other similar concentrations can easily be identified in the future, if faculty interest exists. For example, there already exist very strong programs at least in the following areas: robotics', control systems; precision measurements: manufacturing systems; fluid power systems; vibrations; power electronics. The students will also be expected to complete a senior design project with special focus on one of the areas described above. The Electro-Mechanical Systems Laboratory is but one example of the options available to students interested in pursuing such a curriculum. Finally, the students will select a number of technical electives from the available list of courses in the two participating departments. A possible sequence is indicated below. Core courses • • • • • • •
Introductory Circuits (with Laboratory) Introductory Electronics (with Laboratory l Introduction to Logic Design (with Laboratory) Introduction to Microprocessor Based Systems System Dynamics and Vibrations (with Laboratory) System Dynamics and Electro-Mechanics (with Laboratory) Mechanical Measurements (with Laboratory) Specialization courses
• • • •
Introduction to Mechatronics Dynamics and Simulation of Electro-Mechanical Systems Control of Electro-Mechanical Systems Electro-Mechanical Systems Laboratory; Senior Design Project, to be elected over two or three consecutive quarters.
Further detail oil the three lecture courses, which have been specially developed or modified to be part of this program, is supplied in the Appendix. Technical electives Students in the program will be required to complete 9-15 quarter hours of technical electives to be chosen among the following and other existing courses: • • • • • • •
Machinery Dynamics and Vibration Measurement System Application and Design Applied Digital Control Fluid Power Systems Mechanical Design of Manipulators and Robots Microprocessor Laboratory Introduction to Real-time Robotics Systems.
Several other relevant courses are available in both Departments.
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2. Laboratory The Electro-Mechanical Systems Laboratory is designed to expose the students to the electrical, electronic, mechanical, hydraulic and software aspects of mechatronic systems. Applications that will be studied in this laboratory will include: an electromagneto-mechanical proportional effort steering system; an anti-lock braking system; a hydraulic load; a flexible shaft with inertia and friction loads; hydraulic systems; and electric and hybrid-electric vehicle applications. The laboratory, which is already partially operating, includes a number of experiment stations, including a small internal combustion engine and various electric machines, such as induction, synchronous, D.C., and switched reluctance motors. Each station is or will be equipped with either a Motorola DSP 56000 Digital Signal Processor or a Motorola MC68332 microcontroller development system. Workstations are available for data acquisition, simulation studies and data processing. The laboratory will function as an open laboratory, available to the students for their design projects. It is expected that a formal laboratory course will be developed in the future. Additional laboratory facilities for special projects are also available in the OSU Center for Automotive Research. The existing experimental facilities reflect the interests of the industries currently sponsoring the program (see Acknowledgements). It is expected that the majority of the senior design projects will be industrysponsored.
3. Design projects The design projects will be realized through the use of open laboratories and with the participation of industrial sponsors, who will assist in defining projects and will provide in-kind and cash support for individual projects. Listed below are some sample projects that are currently in progress.
Formula Lightning TM electric race car. This project involves the design, analysis and testing of an electric open-wheel race car. The student-designed propulsion and energy storage systems were tested in inter-university competitions in 1994 and 1995. Projects have included: vehicle dynamics and race track simulation; motor and battery pack selection; battery pack and loading system design; and transmission and driveline design. This is an ongoing competition, and new projects are defined in advance of each race season. Four races are scheduled for 1995. The OSU vehicle was the winner of the 1994 Electricore Inaugural Formula Lightning Race at Indianapolis Raceway Park. This race was nationally televised on ESPN. A number of industrial sponsors funded this event. Design of an electro-mechanical valve for power steering system. If the camshaft of an automobile or the hydraulic rotary valve used in the power steering system could be replaced by an electro-mechanically controlled valve, the car would run more efficiently. The objective of this project is to design a laboratory scale model of an electro-mechanically controlled valve to be operated with a Motorola M68HCllE9 microcontroller. This project will consist of the design of a solenoid operated valve, a power converter to provide the power needed by the valve and a base drive board.
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The microcontroller will be interfaced with the drive base board for control of the power converter that will control the solenoid valve. The control software will reside in the microcontroller for the operation of the valve that will permit the study of various control strategies.
Design of a fuel injection system :or small utility engines. The aim of this project is to design a fuel injection retrofit system for a small utility engine based on the Motorola MC68332 microcontroller. New regulations issued by the U.S. Environment Protection Agency require that small engines begin to comply with the environmental standards currently imposed on passenger and commercial vehicles. This project will include the design of the fuel injector driver electronics and of a control software development system that will permit rapid prototyping of different fuel control strategies.
CREATING A PIPELINE
One of the difficulties in the establishment of new programs is in attracting a sufficient number of students to the program, so that critical mass is established. To provide motivation to enter a program that is likely to be more challenging than the conventional BSEE and BSME curricula, some special incentives have been created, based on industrial support, internal (College) support, and on the facutty's own research programs. These include the following. • Use of the College of Engineermg Honors Program and of numerous available scholarships to support students through their senior year. • Use of National Science Foundation Research Experience for Undergraduates* grant program to provide student support. • Use of industry-supplied scholarships to recruit promising students, with special consideration to women and minorities. • Summer internships in industry, provided by industrial sponsors.
PROGRAM EVALUATION
The curriculum program described in the preceding sections will be assessed and evaluated by two principal means. The first consists of an Industry-University Advisory Board, which will advise and guide the course and laboratory development. The members of the advisory board will be as follows. (1) The Chairs of each Departtnent, cx .ffficio. (2) One faculty with significant experience in Electro-Mechanical Systems from each Department. (3) A board of industrial advisors. Current members of the advisory board are from: Chrysler Corporation: Ford Motor Company: General Motors (three divisions): Liebert: Reliance Electric: Motorola. *This program provides funds for the support of undergraduate students to NSF research grant recipients.
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The second means of evaluation consists of a statistical survey done be specialists (i.e. from the O S U School of Education); the statistical survey will track students in the program, as well as a control group of engineering students not enrolled in the certificate program. Questionnaires will be designed by the evaluation team in collaboration with the industrial sponsors, with the aim of establishing relevant measures. In the last year of the study, students who have graduated from the program, as well as a control group, will be asked to fill a separate questionnaire aimed at determining the success of the program in preparing engineering students for their careers.
CONCLUSION The project described in this paper incorporates the major elements which lie at the core of the engineering education mission in the 21st century*: (i) a new emphasis on basic engineering for design and production; (ii) the integration of mechanical, electronic and computational systems; (iii) multi-media tools to provide a more flexible learning environment; (iv) an environment in which the undergraduate education process naturally integrates with research activities, thus fostering the transfer of ideas and expertise from research to education. The alliance between industry and university that is outlined in this paper should be a natural one in engineering education; we hope that in time the O S U program may serve as a model for the development of a new generation of electro-mechanical engineers with truly interdisciplinary skills. It is hoped that the educational initiative undertaken by these authors provides a building block towards a comprehensive Mechatronics program at OSU. Acknowledgements--The work described in this paper has been supported principally through a grant from the National Science Foundation Division of Undergraduate Education, and with matching equipment and in-kind contributions from the OSU Center for Automotive Research, the OSU Office of Research, the Departments of Electrical and Mechanical Engineering, and the OSU Engineering Experiment Station. Cash and equipment gifts from Ford Motor Company, General Motors Corporation, Liebert, Reliance Electric and Motorola, Inc., are alsogratefully acknowledged. Finally, the authors would like to thank the sponsors of the Formula Lightning~ electric race car: Ohio Semitronics, Inc.; General Motors; the International Brotherhood of Electrical Workers, Local 683; PPG; Transportation Research Center, Inc.; Ohio Aerospace Institute; Edison Welding Institute; Honda of America; Taylor Race Engineering; Watterson Industries; Electric Vehicle TechnologyCompetitions, Inc.; Electricore.
REFERENCES 1. Bradley D. A., Dawson D., Burd N. C. and Loader A. J., Mechatronics, Electronics in Products and Processes. Chapman & Hall, London (1991). 2. Rizzoni G. and Keyhani A., Design of Mechatronic Systems: an integrated, inter-departmental curriculum. In Proceedings of First Workshop on Mechatronics Education, Stanford, CA, 21-22 July (1994). 3. Carryer J. E. (Ed.), Proceedings of First Workshop on Mechatronics Education, Stanford, CA, 21-22 July (1994). 4. Rizzoni G., Principles and Applications of Electrical Engineering. Richard D. Irwin, Burr Ridge, IL (1993). *Based on the keynote address given by Dr Charles M. Vest at the 1992 annual conference of the ASEE.
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G. R I Z Z O N 1 and A. K E Y H A N I
APPENDIX INTRODUCTION
TO MECHATRONICS
Course objectives The aim of this course is to supply basic background in the areas of multi-domain systems (including fluid, thermal, mechanical, electro-mechanical, electronic). Among the topics covered are: multi-phase A.C. power, power electronics, and digital computer interface. The course summarizes specialized material necessary to understand the operation of electro-mechanical systems which is currently not covered in the ME curriculum, and which is scattered among several courses in the EE curriculum. The material presented in the course is subdivided into three main sections: (i) modeling hybrid systems; (ii) signal conditioning and digital computer interface fundamentals; and (iii) power electronics for industrial applications. During the course various case studies will be presented to illustrate the application of modern electronics to mechanical systems. These exercises will take advantage of computer-aided tools such as SABER/Analogy which permit the modeling of mixed-mode electro-mechanical, electro-magneto-mechanical and electro-hydro-mechanical systems. At the conclusion of the course the student will be able to analyze and specify electronic systems with application to the control of industrial machinery using state-of-the-art computer aids. Student performance will be assessed through examinations (one midterm and one final exam), and through homework assignments, including computer-aided design problems.
Text Rizzoni G., Principles and Applications of Electrical Engineering. Richard D. Irwin, Burr Ridge, IL (1993). Rizzoni Q., Class notes, The Ohio State University, Columbus, OH.
Reference SABER/Analogy user's guide, Analogy (1992).
E L E C T R O - M E C H A N I C A L MOTION DEVICES Course objectives The purpose of this course is to provide a basic knowledge of electro-mechanical motion devices for mechanical and electrical engineering students interested in electro-mechanical systems, robotics and control. To achieve this objective, considerable attention is given to electro-mechanical rotational devices commonly used in automated control systems. The course summarizes background material needed for mechanical engineering students to understand the operation of electro-mechanical motion devices. The material presented in the course consists of the following sections: (a) magnetic circuits; (b) electro-mechanical energy conversion; (c) state space model representation; (d) design of magnetically coupled windings; (e) dynamic models of D.C. machines; and (f) A.C. electro-mechanical motion devices. During the course various problems are assigned to study the dynamic performance of electro-mechanical motion devices. The problems are studied using computer-aided design tools of the Matlab software system. Student performance is evaluated through five simulation problems and one midterm and a Final exam.
M O D E R N CONTROL OF INDUSTRIAL ELECTRIC MACHINES Course objectives The aim of this course is to provide basic knowledge of modern control techniques used for control of industrial electric machines as part of electro-mechanical systems such as electric vehicles and manufacturing systems. The course is presented from a system viewpoint with the objectives to provide knowledge needed by mechanical and electrical engineering students for designing electro-mechanical systems using industrial electric machines. The material presented in the course consists of the following sections: (a) electric motor drive systems; (b) modeling of the three-phase A.C. machines in arbitrary reference frames; (c) simulation of power
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converters; (d) modeling of Pulse-Width-Modulated (PWM) Inverters; (e) current control of PWM inverters; (f) A.C. drives' stator voltage and frequency control; (g) vector control and flux weakening control. During the course six simulation problems are assigned to study the control of an A.C. machine supplied from a power converter using various control techniques. The problems are studied using computer design tools of the Matlab software system. Students' performance is evaluated through six simulation problems, one take home midterm and a final exam. Text
Krause P. and Wasynczuk O., Electromechanical Motion Devices. McGraw-Hill, New York (1989). References Power Electronics and A C Drives. Prentice-Hall, Englewood Cliffs, NJ (1986). Keyhani A., Class notes.